Designing with Ada for satellite simulation: A case study

A FORTRAN-operated and an Ada-oriented design for the same system are compared to learn whether an essentially different design was produced using Ada. The designs were produced by an experiment that involves the parallel development of software for a spacecraft dynamics simulator. Design differences are identified in the use of abstractions, system structure, and simulator operations. Although the designs were significantly different, this result may be influenced by some special characteristics discussed

An approach for assessing software prototypes

A procedure for evaluating a software prototype is presented. The need to assess the prototype itself arises from the use of prototyping to demonstrate the feasibility of a design or development stategy. The assessment procedure can also be of use in deciding whether to evolve a prototype into a complete system. The procedure consists of identifying evaluations criteria, defining alterative design approaches, and ranking the alternatives according to the criteria

Designing with Ada for satellite simulation: A case study

A FORTRAN oriented and an Ada oriented design for the same system are compared to learn whether an essentially different design was produced using Ada. The designs were produced by an experiment that involves the parallel development of software for a spacecraft dynamics simulator. Design differences are identified in the use of abstractions, system structure, and simulator operations. Although the designs were vastly different, this result may be influenced by some special characteristics discussed

MULTIPLE SPATIAL SCALE ANALYSIS OF WHOOPING CRANE HABITAT IN NEBRASKA

Geographic Information System (GIS) and remote sensing technologies were used to evaluate whooping crane stopover habitat in Nebraska. The goal of the research was to investigate habitat selection at multiple spatial scales. The GIS database consisted of all confirmed whooping crane sightings reported in Nebraska from 1975-1996 and land cover information delineated from color infrared aerial photographs and Landsat Thematic Mapper data. Results suggest that whooping cranes select roost habitat by recognizing site-level and landscape-scale land cover composition. Wetland is the most strongly selected habitat type at all spatial scales examined. This presentation emphasizes methods used to analyze habitat selection and how the information can be applied in conservation

Concept design and alternate arrangements of orbiter mid-deck habitability features

The evaluations and recommendations for habitability features in the space shuttle orbiter mid-deck are summarized. The orbiter mission plans, the mid-deck dimensions and baseline arrangements along with crew compliments and typical activities were defined. Female and male anthropometric data based on zero-g operations were also defined. Evaluations of baseline and alternate feasible concepts provided several recommendations which are discussed

The Role of Social Media and Product Differentiation in Etsy Micro-Manufacturing Shops

This research presents an analysis of online micro-manufacturers who sell their handmade and individually customized products by means of the Internet. Using extant literature in the areas of social media and long-tail marketing, this study develops a theoretical model of micro-manufacturing item sales success. In this model, we posit that higher average sales prices for items are associated with the dual aspects of social media proficiency and hyper-differentiation. To examine this model, we present an empirical analysis of a dataset consisting of the marketing and sales activities of 1,386 micro-manufacturers within Etsy, an online commerce platform. Results of the analysis show that micro-manufacturers who achieve greater social media recognition and those who leverage their core competencies around handmade and customized products command higher product sales prices. Therefore, our study offers insights for existing micro-manufacturers and researchers interested in examining the way that niche market micro-manufacturers achieve success online

Critical Success Factors in Online Multi-Platform Outpost Marketing Strategies

Companies, especially small businesses, increasingly rely on marketing activities through multiple social network sites. Social network sites provide access to large customer bases and greatly streamline the costs and technical expertise required to engage in electronic commerce. Research interest focused on the nature of small business e-commerce success has understandably increased in recent years to reflect this new aspect of digital business. Many studies in this area look at individual social network platforms like Facebook, Twitter etc. and attempt to examine the factors that correlate with marketing success. While these studies offer important insight into the challenges faced by small businesses in this area, many studies of a single platform fail to take into account the rapidly increasing variety of social network platforms available to small businesses. It is common today to see a single business participating in multiple social network \u27outposts\u27, or digital spaces within social networks from which companies engage in marketing activities. From a strategic standpoint, each outpost offers unique and valuable customer engagement opportunities. For example, traditional social networks like Facebook have huge advantages in terms of size and scope of their user-base, yet marketing strategies designed to take advantage of these characteristics may vary significantly from new image-based platforms such as Pinterest or Instagram. To succeed in such a complex environment, companies necessarily must incorporate a mix of different techniques and strategies designed to capitalize on the strengths, and offset the weaknesses, of each distinct platform. Researchers can inform marketing strategies to the benefit of many companies. Yet to date the research remains fragmented. Specifically, little research categorizes different outposts in terms of their marketing potential and characteristics, or considers the disparate factors that create successful companies in each outpost. This is the gap filled by this study. We collected data from 100 companies across a mix of four different social network outposts for nine weeks to identify the key factors that determine sales success. Our preliminary empirical analysis shows that critical success factors differ considerably based on interactions between core social network characteristics and a company\u27s product offerings, as well as other factors such as geography, company size and company reputation. Results of the study offer numerous takeaways for both companies that seek to understand the social media challenges that they face as well as social network designers looking to succeed in an increasingly competitive social network ecosphere

Ballistic thermal conductance limited by phonon roughness scattering: A comparison of power-law and Gaussian roughness

In this work, we have investigated the influence of power-law roughness on the ballistic thermal conductance KTH for a nanosized beam adiabatically connected between two heat reservoirs. The sideways wall beam roughness is assumed to be power-law type, which is described by the roughness amplitude w, the in-plane roughness correlation length ξ and the roughness exponent 0≤H≤1. Distinct differences occur in between power-law and Gaussian wall roughness. For power-law roughness with low roughness exponents H (<0.5), the influence of phonon scattering can be rather destructive leading to significant deviations from the universal conductance value for flat beam walls. On the other hand for large roughness exponents (H>0.5) the conductance drop is significantly smaller than that of Gaussian roughness assuming similar roughness ratios w/ξ.

Cryogenic microstripline-on-Kapton microwave interconnects

Simple broadband microwave interconnects are needed for increasing the size of focal plane heterodyne radiometer arrays. We have measured loss and cross-talk for arrays of microstrip transmission lines in flex circuit technology at 297 and 77 K, finding good performance to at least 20 GHz. The dielectric constant of Kapton substrates changes very little from 297 to 77 K, and the electrical loss drops. The small cross-sectional area of metal in a printed circuit structure yields overall thermal conductivities similar to stainless steel coaxial cable. Operationally, the main performance tradeoffs are between crosstalk and thermal conductivity. We tested a patterned ground plane to reduce heat flux.Comment: 3 pages, 3 figures, submitted to The Review of Scientific Instrument